When on song, Rohit Sharma can overshadow Virat Kohli. But that happens only in limited-overs formats when the Indian team wears the blue jersey. In Test cricket, Rohit Sharma's stop-start career is still in turbulence mode.

His failures in the recent Test series in South Africa is a reminder of the fact that Rohit is yet to find the 'test' key to success. The Mumbai batting star now averages nearly 40 in Test cricket but that's on the back of some big runs at home. Rohit has not yet played a knock that would show the world he has come of age in Test cricket.

Like millions of others, Australian cricket legend Ian Chappell is also a member of the Rohit Sharma fan-club. However, he is disappointed with Rohit's failures in Test cricket.

"Rohit Sharma has been one of my great disappointments. When I first saw him in a few one day games in Australia in 2007-08 and the way he played the short pitched delivery, I said to myself, 'This guy is a very good player and he will be good in all conditions'. He has been very good in limited overs cricket, particularly in ODIs. I mean, how can you score 264 in a 50-over game? He is a terrific player with all the ability. The disappointment for me is he hasn't produced the goods in Test cricket," Chappell told India Today.

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Rohit's way of dealing with the constant scrutiny around his test disappointments has been to publicly say he doesn't think as much about it. But his comments between the test and limited overs series in South Africa suggest he is striving hard. "You need to tell yourself that the shots you played in tests and the shots you play in odis are different. In odis you think two steps ahead and want to put pressure back on the bowlers," he had said.

Chappell feels Rohit could be suffering from a mental block in the longest format. "I wonder if he hasn't worked out what sort of player he is in Test cricket. I also wonder if batting behind Virat Kohli is a problem for him. In saying that, I am likening his situation with Gordon Greenidge and Viv Richards. Gordon didn't know how good a player he was. He would play really well and when Viv came in he, thought Viv got all the publicity and it diminished him as a player. I am just wondering if that gets in Rohit's mind a bit," he wonders.

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Those in the know of Indian cricket are well aware of the mutual respect between Kohli and Rohit. The Indian captain has admitted to being in awe of some of Rohit's innings. But Chappell's suggestion and Rohit's comments do indicate towards a possible lack of confidence on his part in Test cricket.

Chappell, in fact, has an interesting suggestion. Why not try Rohit at No.3 in Tests, ahead of Kohli? "I thought if he came in at No.3, it might help him. I mean the talent that he has got, he should be one of the best Test players around," he says.